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Wireless implant able to track eye pressure in real time

California Institute of Technology (Caltech) researchers have engineered an eye implant that can detect and wirelessly transmit eye pressure data.

Now, the scientists have their sights on furthering the technology with a device that drains eye fluid to alleviate eye pressure for glaucoma sufferers.

The implant – smaller than a 5c piece – contains a pressure sensor, antennae, and control circuitry. It can be implanted on the sclera to avoid impeding vision, with accelerated lab tests revealing it can stay in place for up to four years.

The device doesn’t contain a battery, making it small and long lasting. Radio waves from a handheld scanner are received by the antenna, which generates a small voltage that temporarily powers the device. It then takes a pressure reading and sends the signal back to the reader.

“With our wireless implanted device, a patient could read their eye pressure any time, as often as they want,” Caltech researcher Mr Abhinav Agarwal said.

“Catching elevated eye pressure early would allow the doctor to modify the therapy if necessary to prevent further loss of vision.”

Previous attempts to develop a similar prototype failed to last more than a month due to problems, including body fluids causing corrosion and tissue growth affecting sensors.

The research team overcame this by enclosing the device in a special silicone-oil bubble coating covered by a biocompatible polymer called parylene.